[HN Gopher] PFAS ban affects most refrigerant blends
___________________________________________________________________
PFAS ban affects most refrigerant blends
Author : doener
Score : 94 points
Date : 2023-03-02 16:32 UTC (6 hours ago)
(HTM) web link (www.coolingpost.com)
(TXT) w3m dump (www.coolingpost.com)
| empyrrhicist wrote:
| While we were waiting for a contractor to replace our failing AC
| and furnace, he had to come back like four times to recharge the
| system (supply chain issues getting the new unit). Now I wonder
| how much refrigerant we were unintentionally breathing, and how
| much PFAS we were bio-accumulating during that time.
| ben7799 wrote:
| If you read that article carefully you probably don't have PFAS
| in your system. It would have to have been replaced in the last
| 10 years to possibly have it.
|
| The older stuff had HFCs/CFCs but didn't have PFAS.
|
| I am in the same situation. My system has had to be recharged
| every 2 years or so but has not failed yet. Overall we're
| talking very small amounts leaked on mine.
| LazyMans wrote:
| I wouldn't worry about it, these gasses are included in the
| blanket PFAS classification, but they are fundamentally
| different and thus non-toxic. r134a, a common refrigerant, and
| likely what your system uses if it's less than 10 years old, is
| used in inhalers.
| rootusrootus wrote:
| > r132a, a common refrigerant
|
| Are you thinking R134A? IIRC, R132A theoretically exists but
| nobody makes it. And R134A is an automotive refrigerant. Most
| residential systems in the last 10 years likely use R410A
| (which is itself a mixture of R32 and R125). That is getting
| phased out and generally replaced with plain R32, as far as I
| know.
| martijnvds wrote:
| R32 is also on its way out, and new units here in Europe
| tend to come with R290 (propane)
| jabl wrote:
| That's interesting, a had an AC unit installed 2 years
| ago (in Europe), and then many units were marketed as
| using the new R32 instead of the traditional R410A.
|
| Now that I look at the website of the company that did
| the installation, it seems all their AC models now use
| R32.
| rootusrootus wrote:
| I have heard a lot about R290 but at least in the US, I
| am not seeing much of a push to go there. R32 is an A2L
| refrigerant and (according to the article) isn't affected
| by the PFAS ban. In the US at least it looks like the
| main choice for the future, at least in the near term.
| LazyMans wrote:
| Sorry, 134a yes
| a1371 wrote:
| Then why are they banning R134A as the article says?
| akira2501 wrote:
| Glaxosmithkline loves it when they do this, it allows
| them to create a new propellant forumlation, and then
| that allows them to put basic asthma medication back on
| patent.
|
| And the current R134a patents are just set to expire.
| Inhalers which should cost $5/ea are set to be $90/ea
| again.
|
| This is the same thing they did when CFC were banned and
| they switched from CFC to R134a. This is a medication
| that should have been off patent decades ago, but due to
| this "trick", it almost certainly never will be.
| kragen wrote:
| at some point this kind of luddism will become self-defeating; we
| can only hope that it doesn't engulf the whole human race
|
| this is banning the safest refrigerants, forcing either a switch
| to dangerously inflammable refrigerants or to systems without
| refrigeration
| VLM wrote:
| The meta goal of greenwashing means you can't use Peltier
| coolers as it would take insane amounts of power to replace a
| condensing fridge, like dedicated circuit 15 amps. They're very
| inefficient... if you're burning coal. What if you're not
| burning coal?
|
| Consider this loophole... imagine a crappy anti-green energy
| wasting Peltier cooler connected to a solar panel. Half the day
| it chills down to -70C and then all night long it slowly warms
| up to -50C until sunrise. Probably the bottom quarter of the
| fridge is a giant ice block with fans blowing on it when the
| fridge above warms up, whereas the cooling is solar and below
| and is on full blast whenever the sun is up.
|
| Minor problem is now you're dumping 1500 watts of heat into
| your kitchen whenever the sun's up. Nice in the winter, not so
| much in the summer. And some idiot is going to gain access to
| the cold-sink to "chill their vodka" and end up with frostbite
| when they touch the -70C sink. And good luck periodically
| defrosting that beast. But, in general, its not an overly crazy
| idea.
| ilyt wrote:
| No, it is utterly terrible solution, as even the worst
| refrigerant beats peltier coolers.
| VLM wrote:
| My point is even the best refrigerant powered by coal or
| even "rando outlet power on average" is less green than the
| worst Peltier cooler powered by a solar panel. So as per
| OPs original claim that if we ban every chemical more
| hazardous than distilled water we can have no refrigeration
| is not entirely true, we can in theory redesign the entire
| system around not using any refrigerants.
|
| It would be an environmental disaster if not powered by
| solar, or maybe wind, of course, but it would technically
| work.
| kragen wrote:
| i agree that tecs are a plausible solution for some
| applications, and i have in fact lived in a house with a
| small tec-driven refrigerator, but phase-change energy
| storage or tces are more viable solutions to the daily energy
| storage problem than the sensible-heat energy storage
| approach you suggest, among other things because the large DT
| you suggest would entail an absurdly large stack of tecs
|
| you can solve the waste heat problem by putting the tecs
| outside and running a coolant loop through the wall, filled
| with brine or propylene glycol; in the case of pces, the
| chilled coolant from the tecs freezes the ice inside your
| kitchen, in the ice reservoir which is used to cool the
| icebox
|
| tces systems (not to be confused with tecs) can be driven
| directly by solar heat rather than through pv
|
| however, i am not convinced that tecs are a viable
| alternative to vapor-compression refrigeration in general
| smt88 wrote:
| Banning harmful substances isn't luddism. What do you think
| luddism is? What is the harm of this ban?
| dsfyu404ed wrote:
| You know why these substances exist right? Because the prior
| substances were cutting a hole in the ozone layer. And at the
| time the new-then substances weren't proven bad yet.
|
| And those ozone eating substances themselves came about
| because the prior refrigerants were more flammable or
| poisonous and the then-new substances were not yet proven
| bad.
|
| It's an endless game of whack-a-mole.
| slackdog wrote:
| > _You know why these substances exist right? Because the
| prior substances were cutting a hole in the ozone layer._
|
| Refrigeration may end up back where it originally started
| (before freon even), using ammonia. Ammonia is somewhat
| dangerous on a local level (you don't want an ammonia leak
| in your house..) but AFAIK it doesn't eat up ozone and the
| local hazard is something that can be mitigated with the
| right sort of product design.
| labcomputer wrote:
| > Ammonia is somewhat dangerous on a local level
|
| Like saying that the Ohio train disaster may cause lung
| irritation, that quite undersells the problem.
|
| Ammonia refrigeration is inherently dangerous and has
| been banned from domestic refrigerators for a long time
| for good reason. Some regulations are written in blood.
| slackdog wrote:
| I think it could be possible to use ammonia in domestic
| refrigerators safely if appropriate measures were taken.
| Particularly, require that refrigerators be installed
| with vent pipes leading from a tamper-resistant enclosure
| straight to the outside. Such vents would be similar to
| those used in waste plumbing to protect people from toxic
| sewer gasses like hydrogen sulfide:
| https://en.wikipedia.org/wiki/Drain-waste-vent_system
|
| But jabl is probably right and something like propane
| would make more sense.
| jabl wrote:
| I don't think we'll see ammonia used in domestic
| refrigeration. Industrial use, sure.
|
| I think what we'll see for domestic refrigerants
| (refrigerators, AC, heat pumps) is hydrocarbons like
| propane or butane (already a reality for refrigerators in
| most of the world), and in some cases CO2.
| kragen wrote:
| i went to a hotel with an ammonia refrigerator in the
| kitchen a couple of weeks ago
| oliveshell wrote:
| Yeah, ammonia is very common in industrial refrigeration,
| especially big specialized systems that need tons and
| tons of refrigerant, as illustrated by this famous
| accident in which 30,000 lb. of the stuff was released:
|
| https://www.csb.gov/millard-refrigerated-services-
| ammonia-re...
| kragen wrote:
| this was a 60-liter fridge with 117 grams of ammonia in
| it in the kitchen of the hotel suite
| FourHand451 wrote:
| I don't think any of this is alarming. Nor a reason we
| should stop trying to solve new problems as we learn of
| them.
| dsfyu404ed wrote:
| I'd rather be exposed to the known-known of propane
| refrigeration in my consumer devices (car, window unit,
| refrigerator, mini-split, etc) than risk exposure poorly
| understood chemicals to reduce the chances of a
| refrigerant fire from one tiny decimal per capita per
| lifetime to a slightly smaller tiny decimal per capita
| per lifetime.
| mustacheemperor wrote:
| It sounds like an endless march of gradual forward
| progress, since each generation of refrigerants has been
| less destructive that the one before.
| dymk wrote:
| How do you feel about leaded gas?
| kragen wrote:
| leaded gas should be limited to extremely low-volume
| applications, because it's enormously harmful
|
| this regulation is more like banning unleaded gas
| hadlock wrote:
| There are better octane boosters, the only reason lead was
| used was because it was marginally cheaper.
| dymk wrote:
| But it's not like unleaded gas. Evidence has been mounting
| that PFAS are the modern 21st century's lead, hence bans
| like this.
| kragen wrote:
| privacy invasion and this kind of discourse are the 21st
| century's lead
|
| there are pfas that are pretty bad but the refrigerants
| in question are not among them
| DoneWithAllThat wrote:
| Snark doesn't do anything but virtue signal.
| kragen wrote:
| i think it's a reasonable question directed at clarifying
| their understanding of my position
|
| or anyway a person who wanted to clarify their
| understanding of my position could very reasonably ask that
| question
| nordsieck wrote:
| > How do you feel about leaded gas?
|
| I think it should be banned.
|
| Sadly, aviation has enough political muscle that they're
| still allowed to use it. Which is amazing to me, given lead's
| extremely harmful effects.
| cypress66 wrote:
| Do you really think the people flying their small cessna
| with 100LL have so much political muscle? I strongly doubt
| so.
| jeffbee wrote:
| It's not the pilots alone, it is also the piece-of-shit-
| airplane industry which employs a handful of people here
| and there, enough to have a little suction in Congress.
| jabl wrote:
| Also GA is, in the end, a relatively small-scale
| activity, so leaded avgas isn't much of a public health
| hazard like leaded automotive gas was back in the day.
| More of an occupational hazard for people working on and
| flying those planes, and higher maintenance requirement
| on the engines.
|
| Hopefully they can manage to roll out G100UL at scale so
| 100LL can finally die. And then that final TEL plant on
| the planet can be shut down for good.
| r00fus wrote:
| Let's not forget those small airports where nearby
| residents are at higher risk due to leaded avgas. That's
| why small airports have been forced to close.
|
| Get rid of leaded avgas and we can have less municipal
| airports closures.
| slackdog wrote:
| The general aviation industry is protected because it's
| part of the pilot training pipeline, and that is
| important because airplanes (both commercial and
| military) have a great deal of importance to governments.
| About 5% of the American GDP is attributed to commercial
| aviation. Compare that figure to the number of deaths
| caused by leaded avgas, and you don't need conspiracy
| theories to explain the outcome.
| outworlder wrote:
| > Sadly, aviation has enough political muscle that they're
| still allowed to use it.
|
| Does it? GA is a shadow of its former self.
|
| There's already a substitute. But it's precisely how small
| general aviation has become that's stifling the transition.
| The volume of avgas made today is already pretty small,
| compared to other gas users, and there's ony a handful of
| plants that can make it. Then there's all the small
| airfields with existing avgas pumps.
|
| Without a big push, it will take time. The fastest way
| would be with a carrot; the stick can come later.
| StillBored wrote:
| Is it time to admit that maybe the problem with r22 and some of
| the other CFC's were that people were using them as propellants
| for hairspray/etc, as canned air, and any number of industrial
| processes (packing peanut manufacture) that was basically blowing
| it into the atmosphere and the lack of regulations requiring
| refrigeration units to be repaired/leakchecked before pumping
| more refrigerant into them?
|
| It seems pretty clear that the fairly short lived damage they
| cause to a renewable resource (ozone) would largly be a non issue
| given modern refrigerant regulations. While the advantages make
| them pretty much the best in any number of areas.
| TheJoeMan wrote:
| You are following the explanation for the bans as they are
| told.
|
| R134a was introduced in the 90's, and in 2010's it conveniently
| is named bad at the same time the patent runs out.
|
| So the savior was the 4x as expensive R1234yf, introduced 2012.
| Don't worry that it's flammable.
|
| Here we are 10 years after R1234yf, it's time to explain why it
| can't be used anymore!
| inportb wrote:
| > R152a also falls outside the PFAS definition.
|
| Oh, so it might be possible to use the contents of "canned air"
| gas dusters as refrigerant.
| CamperBob2 wrote:
| Yep. Turn one of those cans upside down and spray it, and
| you'll see how that works very quickly.
| [deleted]
| iosono88 wrote:
| [dead]
| londons_explore wrote:
| Whats wrong with R600a (isobutane)?
|
| It can provide heating/cooling suitable for nearly all usecases
| in homes, offices and retail (ie. -100C up to +150C).
|
| It isn't awful for the environment if vented (no ozone depletion,
| greenhouse effect less bad than driving your car a few miles if
| you vent a fridge/freezer).
|
| Yes, it is flammable... But in typical quantities in a fridge
| (perhaps 60 grams), it's hard to do too much damage.
|
| It is also cheap, easy to lubricate, unpatented, made by many
| suppliers and efficient.
|
| I really don't understand why anyone would want to use anything
| else....
| akira2501 wrote:
| Every flammable refrigerant I've seen is usually in a
| completely sealed system. There is no way to maintain them
| unless you completely vent the system and add ports yourself,
| manufacturers don't seem to want the liability and many
| governments force the issue by code anyways.
| londons_explore wrote:
| You typically need to completely vent the system for any
| maintenance on a refrigeration system anyway, if only for the
| fact it is important to weigh the amount of refrigerant (too
| much and you could get slugging, which is very expensive to
| fix).
|
| I think lack of ports is simply to save money - in the
| factory it's just as easy to fill once and crimp the system
| closed.
| akira2501 wrote:
| > You typically need to completely vent the system for any
| maintenance on a refrigeration system anyway
|
| On residential/small systems where it's commonly used
| today, sure. For larger systems this is not true. You're
| typically going to have a receiver and a valve you can use
| to store the charge entirely in the receiver. Then you can
| work on the system without having to dump or capture that
| charge.
|
| It also allows you to have additional cooling circuits, so
| you're starting to see this incorporated into smaller
| commercial designs for the additional cooling efficiency.
|
| > I think lack of ports is simply to save money
|
| They're required to be hermetically sealed in the US by IEC
| and in most Pacific Island countries by law where they're
| more commonly used in residential applications.
| NegativeLatency wrote:
| Save money, and force consumers to buy a new one when it
| breaks
| elil17 wrote:
| I'm not an expert in refrigerant selection but you've missed
| many critical aspects of a refrigerant: we care about
| viscosity, density, thermal conductivity, etc. because these
| all impact the energy efficiency of the system.
| zbrozek wrote:
| Several light hydrocarbons seem like perfectly good
| alternatives. Propane is another one. And there's also quite a
| lot of use of ammonia for refrigeration as well. It's not clear
| to me why these simpler, non-chlorinated, non-fluorinated
| compounds are so grossly undesirable that we keep chasing more-
| complex alternatives.
|
| Is it really that people are simply horribly afraid of their
| flammability?
| VLM wrote:
| People are scared of the sealed container explosion.
|
| An external butane leak would be about as harmful as a
| leaking cig lighter.
|
| Internal leak? A perfect mixture of butane and air the size
| of fridge would certainly take out a wall, maybe an entire
| house if it knocks out a load bearing wall.
|
| The worst part about the internal explosion is its almost
| certain to happen when the owner is standing right in front
| and opens the door and the light kicks on along with maybe
| anti-frost heaters or whatever else is in there.
|
| I have seen some ideas proposed such as using the "smart" in
| a smart fridge for good not evil and locking the door if the
| system pressure drops below "X". Much more likely the "smart"
| in a smart fridge will never be permitted to be used for
| anything other than advertising and marketing, which is sad.
|
| Energy content of hydrocarbons is about the same (to one sig
| fig or less LOL) and just one gram of gasoline can blow a
| piston rod clean thru an engine block under perfectly bad
| conditions (already shattered bearings, etc) so a couple
| hundred grams under worst possible case in a confined sealed
| fridge could take out a house, most likely.
|
| (Edited to add: I have a better analogy: A perfect
| stochiometric mix of air and diesel the size of my coffee cup
| can blow the engine head clean off a diesel engine, IIRC
| that's how one of the brothers who invented the Diesel engine
| died in a lab accident a century ago. And that was just a
| little coffee cup sized engine cylinder. So imagine a sealed
| container the size of a fridge instead of a coffee cup...
| that'll take out a house for sure... neighbors will
| "probably" live but I wouldn't bet on it...)
| zbrozek wrote:
| Yet we plumb methane in houses all the time. Also, at least
| for HVAC, it's perfectly reasonable to keep all of the
| refrigerant outdoors and use water as a heat transfer
| medium to the interior.
| amluto wrote:
| And it's not a great idea, especially given the
| proliferation of appliances that burn it in room air.
|
| And methane has the convenience property of being less
| dense than air. I'm not sure, but I expect that the
| heavier hydrocarbon gasses might be more likely to
| accumulate indoors.
| ajb wrote:
| I get your point, but we already have methane pumped to our
| houses. Are these worse?
| VLM wrote:
| Yes, sealed container vs open air. If we stored natgas in
| scuba tanks that could get exciting... ironically there
| are people considering powering auto engines with
| compressed natgas... must be very exciting in a fire LOL.
| ilyt wrote:
| locking might not even be necessary, just power off the
| device if pressure of refrigerant drop.
|
| Having some way to ventilate the gas (so you don't just get
| "a box full of flammable gas" situation on slow leak)
| without reducing performance too much might help also
| gabereiser wrote:
| I had an internal explosion of my gas grill. I apparently
| forgot to turn the gas off so it filled the chambers under
| the grill plates and when I went to light it, it sent the
| top and the grill plates through the lanai and 40ft into
| the air. I lost my eyebrows for a few months.
| carnot wrote:
| [dead]
| SoftTalker wrote:
| Ammonia is quite toxic. Some bad outcomes from leaky ammonia
| air conditioning in the past. Ok for industrial chillers with
| good leak detection systems.
| VLM wrote:
| Texas state code requires machine rooms for ammonia systems
| to get 30 air exchanges per hour, same state building code
| requires houses to be under 1/3 air exchanges per hour.
|
| I'm a little fuzzy about the later, pretty sure about the
| former, and most people don't have the privilege of living
| in Texas (not sure if I'm kidding or not?), but it
| demonstrates the safety issue that ammonia cooling needs
| about a hundred times as much ventilation as a normal
| kitchen. And insert the usual quotes about building codes
| being written in blood so they aren't demanding a hundred
| times the ventilation just for fun.
| nigrioid wrote:
| Flammable refrigerants are no joke:
|
| https://www.youtube.com/watch?v=A169-s4KHFQ
| amluto wrote:
| For better or for worse, people like to pump refrigerant
| through pipes in buildings, and flammability can be a problem.
| Also this requires a lot of refrigerant.
|
| One can separate the refrigeration part and the moving-heat-
| around part, though, by using good old H2O in pipes. Water is
| non-flammable, non-ozone-depleting, cheap, and has zero GWP. It
| can be a bit messy if a large amount spills indoors, though.
| loeg wrote:
| Do the remaining alternatives work, and are they excessively
| expensive?
|
| > Laboratory test equipment and centrifuges would receive a
| 12-year exemption as no alternatives are currently available.
|
| Oh, so there are no remaining alternatives that work in these
| applications.
| arsome wrote:
| Hydrocarbons work quite well and are (comparatively) minimal
| impact on climate change. There's been some paranoia about
| fires, particularly in automotive applications but it's
| actually a quite small amount needed to do the job.
| mschuster91 wrote:
| The problem are large building air conditioning systems,
| grocery store chillers and industrial machines - they contain
| an awful lot of coolant and are _very_ expensive to replace
| which means they tend to last for decades.
| throw_away1525 wrote:
| Ammonia (another dead simple molecule/process) is used in
| these services quite often, as far as I know.
| jabl wrote:
| From what I understand, at least here in Europe CO2 has
| been common in recent supermarket and similar
| installations.
| amluto wrote:
| One can buy large building air conditioners that use water
| to move heat around. There will still be refrigerant
| somewhere in the system, but there won't be long
| refrigerant pipes anywhere.
|
| I don't know how popular these are. I have seen multiple
| condo buildings with a water source heat pump in each unit.
| The usual suspects (Mitsubishi, Daikin, etc) have hydronic
| systems with outdoor heat pumps on their websites. Chiltrix
| markets a small-building solution.
| rsync wrote:
| Why do centrifuges need refrigerant?
| kazinator wrote:
| You probably have to sometimes spin biological materials that
| have to be kept cool.
| rleigh wrote:
| Because they are temperature-controlled and contain a
| refrigeration unit.
|
| In biological and medical applications, you might want to
| have the samples kept cool for stability. You'll transfer
| them from a fridge or on ice into the cooled centrifuge and
| back again after you've spun it down. Since in these big
| units the rotor is often a big hunk of anodised aluminium, it
| also helps maintain temperature stability.
| kube-system wrote:
| There are a lot of alternatives that are cheap and perform
| well... but many of those have other safety concerns.
|
| Some common examples are hydrocarbons or ammonia:
| https://en.wikipedia.org/wiki/Natural_refrigerant
| spqr0a1 wrote:
| Ethane (R-170) is a fine low-temperature refrigerant for lab
| equipment. The performance characteristics are at least as good
| as halocarbon refrigerants. The main drawback is flammability
| but propane has a similar concern and is already widely used in
| residential refrigerators and similar size systems.
| xxpor wrote:
| >widely used in residential refrigerators and similar size
| systems.
|
| Not in the US (because of the flammability), unless
| something's changed very recently.
| xenadu02 wrote:
| > Not in the US (because of the flammability), unless
| something's changed very recently.
|
| I don't know when it changed but R-290 (propane) is allowed
| up to 13oz. My ice maker uses it. I believe it must also be
| sealed without service ports both to prevent leaks and
| prevent anyone from connecting normal A/C service equipment
| to the system. Service requires emptying the system then
| brazing service ports onto the fill pipes (which are left
| much longer than normal for this purpose).
| akira2501 wrote:
| In commercial applications you'll see R-290. It's often
| used in low temperature applications, like ice cream
| display freezers. I've seen them in gas stations and pizza
| shops quite a bit.
| thaeli wrote:
| In the last few years, the US has finally started allowing
| small appliances containing limited quantities of flammable
| refrigerants.
| jabl wrote:
| USA is kind of the exception. In much of the rest of the
| world, propane or butane are the norm in domestic
| refrigerators.
| xxpor wrote:
| Most of the world doesn't build their residential
| buildings out of light wood frame :/
| scythe wrote:
| A fuel-air explosion will not be contained by a
| _reasonable_ amount of concrete or masonry. The real
| safety lesson is to control sources of ignition and
| prevent the buildup of released gases.
| slackdog wrote:
| If your house is on fire, you best GTFO no matter what
| kind of refrigerator you have.
|
| American homes have plenty of propane/natgas appliances
| anyway, so what difference does one more make?
| xxpor wrote:
| People usually store their propane tanks outdoors.
| hn8305823 wrote:
| Notably, Propane has almost identical refrigeration
| characteristics to R-22, so it was an easy drop-in
| replacement for systems designed for R-22 when that was
| banned.
| _a_a_a_ wrote:
| I don't see why, they're hardly less flammable
| RobotToaster wrote:
| From personal experience things using propane refrigerant
| seem to make a high pitched noise, I'm not sure if that's a
| property of the refrigerant or how devices using it are
| built.
| dsfyu404ed wrote:
| There's no "reason" propane has to be louder but most
| propane refrigeration systems are used in industrial or
| cost-conscious applications where making the equipment
| quiet is less of a priority. When designing pumps it takes
| a non-trivial amount of engineering effort to ensure that
| the bulk of the noises emitted are above/below human
| hearing range.
| jrimbault wrote:
| Magnetic refrigeration seems (to a complete layman) to show
| promise.
|
| https://en.wikipedia.org/wiki/Magnetic_refrigeration
| hadlock wrote:
| I remember reading about this in Popular Science in high
| school. Residential refrigerators powered by this technology
| by 2006! Twenty years after that magazine article I haven't
| seen any substantial progress towards a commercial product.
| sargun wrote:
| I for one, hope that someone figures out a way to make this
| cost effective.
|
| I think thermoacoustic coolers are another promising
| solution.
| scythe wrote:
| The problem with most alternative refrigerant technologies
| (magnetocaloric, electrocaloric, thermoelectric) is the same:
| the temperature deltas tend to be rather small, at best 25 C.
| That is roughly the thermal performance of the recently
| published "ionocaloric" cooling system; 20 C is very good for
| a magnetic system. For air conditioning, a delta of 25 C will
| just do (assuming outdoor temperature below 50 C!), but heat
| pumps may need to cross temperature gaps of 40 C or more.
| chicob wrote:
| PFAS are harmful, both to the environment and humans, so the
| transition to safer alternatives is commendable.
|
| The fact that this ban seems to fit the specific blend of a
| particular company, however, casts some doubts on how this
| process was conducted. Specially in a time when demand is
| projected to increase considerably.
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(page generated 2023-03-02 23:02 UTC)